Update can_scramble.rs to fix issue with some inputs
Update can_scramble.rs to fix issue with some inputs

See https://github.com/mre/the-coding-interview/pull/51
mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview,mre/the-coding-interview